Square Washers

When constructing timber, wood and concrete fixings, a larger surface area may be required to evenly disturb load. Unlike round washers, square washers are able to fix firmly a larger surface area. Cromwell stock a selection of square washers in a range of sizes to suit your application from suppliers Qualfast and Workshop.

What are square washers?

Square washers, also known as construction square plate washers, are a thin square shaped plate that has a hole, usually in the centre which is used with nuts, bolts or screws to hold fixings in place and evenly spread the load of threaded fasteners to reduce vibration.

When are square washers used?

Most washers are predominantly disk shaped, however where a stronger resistance is required to prevent a fixing from loosening a square washer is ideal as it has a bigger surface area which can distribute larger loads evenly.

Square washers are often used in all high load applications where a large clamped fixing is needed which can include concrete flooring applications, wood and timber construction or where it is necessary to fix bolts, screws and nuts through walls and timber.

Considerations when choosing a square washer

Diameter  -   Selection of the correct washer to suit the size of your fastener is critical to ensure a strong evenly spread load. There are a range of sizes available which is typically measured in metric.

For Norm Size  -   Consideration to the compatibility of the nominal size of compatible bolt or screw is vital. Also measured in metric.

Material  -   Square washers are available in variety of materials, although mostly in stainless steel. This is due to their excellent resistance to corrosion and durability.

Square washer jargon buster

DIN  -    This is the approval used by the German institute for standardisation. Square washers have several applicable standards.

DIN 436  -    Square washers for wood constructions

DIN 434  -    Square taper washers for U-sections

DIN 435  -   Square taper washers for I-sections


Do I really need a square washer?

Square washers are a vital component in fixing and fastening, they prevent vibration and distribute high load evenly to ensure fasteners remain firmly in place.